The solubility of apricot kernel oil in supercritical carbon dioxide

The solubility of kernel oil from apricots (Prunus armeniaca L.) in supercritical carbon dioxide at 313.15, 323.15 and 333.15 K and at 15, 30, 45, 52.5 and 60 MPa was determined. Appropriate models were fitted to the data and the crossover pressure of apricot kernel oil was found to be between 20 and 30 MPa. Crossover pressure is a pressure value at which the effect of temperature on the solubility changes. Solubility increased as the temperature increased above the crossover pressure but decreased when temperature increased below the crossover pressure. It increased with an increase in pressure over all of the temperature range. The solubility data were well represented by models based on density but the best was found to be the Adachi & Lu equation. An empirical model that did not require density data for CO2 was proposed to relate solubility to temperature and pressure and it was found equally successful to the Adachi & Lu equation.